I’d say it’s about on par, in that the (bad guy) endings both feel kind of unsatisfying, largely because you don’t get a chance to enjoy any of the power you’ve nominally seized. Obviously there are plot reasons for this, but it ends up making the victories feel a bit hollow.
I don’t know if Larian ever had plans to implement class-based stronghold quests à la BG2, but some of the origin character quest lines seem well suited for it. If I had my druthers, there’d be ways for players to take over and run places like the Emerald Grove, House of Grief, maybe the Circus of the Last Days. Could be good expansion fodder, but I haven’t read anything yet about whether they’re working on one.